Crude prices rose today as traders awaited this weekend's summit of key oil producers to discuss freezing output levels and easing the supply glut.
US benchmark West Texas Intermediate for delivery in May was up 28 cents at $40.64 per barrel, having earlier touched a three-week high at $40.91.
Brent crude for June delivery was trading 48 cents higher at $43.31 a barrel. The contract had earlier forged a 4.5-month peak at $43.58.
The oil market had also risen yesterday after soaring 8% or more last week.
A chronic worldwide supply glut sent oil prices collapsing by three quarters in value between August 2014 and February this year, when they struck near 13-year low points.
Analysts expect prices to see-saw before Sunday's meeting in the Qatari capital Doha that will bring together both OPEC producers led by Saudi Arabia and non-OPEC members such as Russia.
A major topic is a proposal to freeze output at January levels to try to ease oversupply.
Barclays Research said the oil market was expected to remain "neutral" until after the April 17 summit.
"We expect better directional momentum after the meeting of OPEC and non-OPEC countries," it said in a commentary.
However, the bank noted that the "current expectation is for their actions to have limited impact given the lack of involvement in the freeze of producers that have the potential to grow output."
Key OPEC member Iran has been raising output since nuclear-linked Western sanctions were lifted in January and has signalled it will not join the freeze calls.
Some analysts have said only a production cut, rather than a mere freeze, could permanently boost prices amid weak demand in the oversaturated market.
